Two weeks ago, Frank J. Williams spoke at the University of Hawai'i's William S. Richardson School of Law. Williams is the chief judge of the U.S. Court of Military Commissions Review. He is a timely visitor, given President Obama's recent orders to close Guantanamo and suspend its military commissions whose trials Judge Williams' court reviews.

In his remarks, the judge mentioned the case of an Afghan detained at Guantanamo for tossing a grenade into an American Humvee. The issue that reached Judge Williams' court was a question of evidence. However, there is a more fundamental question to be asked: Why is this Afghan in Guantanamo in the first place?

I served as an American soldier for nearly 30 years. During my tour in Iraq, six members of my brigade were killed and 23 were wounded — most in incidents somewhat similar to this one. I am not overly sympathetic toward roadside bombers, grenade-tossers and their ilk. However, the rule of law is more important than my life or the lives of my soldiers. Without it, there can be no freedom.

What does international law require us to do with the Afghan grenade-tosser?

In my father's war, the grenade-tosser would have been German. He would have been wearing a uniform and in the service of a nation-state that had declared war on us. If this grenadier survived the engagement and was later captured, he would have been put in a prisoner-of-war camp until Germany surrendered on VE-Day. Then, he would have been repatriated. No one would put him on trial for engaging in combat because that is what soldiers do.

This model worked well in World War II, but we are told that the "Global War on Terror" is a new kind of war requiring a new model. I disagree.

The use of terror as a tool of political change is as old as mankind. No war can eliminate it. Regardless of what we call it, we are not engaged in a war because we are not in combat with the forces of a nation-state. In 1647 the Treaty of Westphalia established the principle that war is the exclusive prerogative of recognized nations. If the U.S. Air Force bombs Paris, that is war. If I decide to plant a bomb in Paris, I may call it war, but it is a crime, plain and simple.

Our nation may engage in campaigns of "regime change," but once new sovereign governments take the place of those deposed, the war has ended, even though military operations may continue. What happens thereafter may be combat, but it isn't war, at least not in a legal sense.

So let's return to the Afghan grenade-tosser. The United States made war on Afghanistan. Its Taliban government was entitled to resist us. It did; it lost; and there is now a new Afghan government, whose sovereignty we have acknowledged for almost seven years.

If the grenade-tosser was a soldier in the Taliban army before Karzai's government took power, then he is a prisoner of war. He should be repatriated to the new Afghan government. If, however, the grenade-tosser was rebelling against the Karzai regime's post-Taliban partnership with NATO forces, then he isn't a soldier at all. He is a criminal who committed a crime in and against the sovereign state of Afghanistan. Let the Afghan government prosecute him.

Either way, he shouldn't be sitting in an American prison cell in Cuba. I wonder how many of the other 250-odd detainees belong there.

Retired Col. Thomas D. Farrell, a Honolulu attorney, served as an Army intelligence officer in Iraq from June 2005 to May 2006. He wrote this commentary for The Advertiser.